I did some research on your gallery, and came up with some results:
A thumbnail for one of your photos can be accessed and created:
http://www.venrix.com/photos/getfile.ph ... %20462.jpg - but when trying to access the thumbnail it created, I get "forbidden":
http://www.venrix.com/photos/content/an ... %20462.jpg
I'm not quite sure what the problem is, but I imagine it might be related to the script giving created thumbnails incorrect permissions. Can you try the following:
# Delete all thumbnails "tn_*" atleast in one folder for testing.
# Locate the 2 files makethumb.php and getfile.php in the Imagevue root folder. Set their permissions to 777.
I also checked your permissions which should be ok -
http://www.venrix.com/photos/test/dir2.php
If you still can't solve it, perhaps you can provide FTP login and send in a PM so we can dig into this issue?